Kissinger had a low opinion of North Vietnam, saying "I can't believe that a fourth-rate power like North Vietnam doesn't have a breaking point"... In September 1969, Kissinger in a memo advised Nixon against "de-escalation", saying that keeping U.S troops fighting in Vietnam "remains one of our few bargaining weapons". In the same memo, Kissinger stated he was "deeply disturbed" that Nixon had started pulling out U.S. troops, saying that withdrawing the troops was like "salted peanuts" to the American people, "the more U.S troops come home, the more will be demanded", giving the advantage to the enemy who merely had to "wait us out". Instead, he recommenced that the United States resume bombing North Vietnam and mine the coast. Later in September 1969, Kissinger proposed a plan for what he called a "savage, punishing" blow against North Vietnam code-named Duck Hook to Nixon, arguing that this was the best way to force North Vietnam to agree to peace on American terms.